noun
extinct organisms; ancient life
Refers to organisms that lived in the geological past and are now extinct, studied in paleontology.
古生物の化石を博物館で見た。
I saw fossils of extinct organisms at the museum.
彼は古生物学を専攻している。
He is majoring in paleontology.
絶滅 means 'extinction', the process, while 古生物 refers to the extinct organisms.
Compound of 古 (こ, 'old, ancient') + 生物 (せいぶつ, 'living thing, organism').